Electric-lighting system



Patented Apr. 25, I899.

5. 0. noon. ELECTRIC LIGHTING SYSTEM.

(Applioltinu M 1 .1 a, 1897. M. 1m. 17, mm

(In lodel.)

PVT 772/ ATTORNEY.

WITNESSES:

TERS no. wc mmma, WASHINGTON o. c

UNITED STATES PATENT OFFICE.

RALPH O; HOOD, OF DANVERS, MASSACHUSETTS, ASSIGNOR TO THE GENERAL ELECTRIC COMPANY, OF NEW YORK.

ELECTRIC-LIGHTING SYSTEM.

SPECIFICATION forming part of Letters Patent No. 623,607, dated April 25, 1899.

Application filed February 3,1897. Renewed March 17, 1899. Serial No. 709,464 (No model.)

To a, whom it may concern:

Be it known that I, RALPH 0. H001), a citizen of the United States, residing at Danvers, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Electric-Lighting Systems, of which the following is a specification.

My invention relates to electric-1i ghtin g systems in which are and incandescent lamps are both operated from the same source of electricity.

It is well known that to successfully operate arc-lamps across a system of constant potential a considerable resistance in series with the arc is required. Especially is this so when the arc has a high voltage, as in the inclosed arc type of lam p ,probably due to the unstableness of the are under this condition.

The object of my invention is to increase the amount of illumination derived from the electrical energy necessary to operate arclamps under the above conditions by means of converting as large an amount as possible of the heat energy absorbed by the abovementioned resistance into light and also to provide a more constant resistance by so doing, as will hereinafter be explained.

My invention therefore consists in an electrical resistance possessing the power of light, which I have found best produced in the incandescent lamp, an electric-arc lamp requiring a series resistance, and'a regulating magnet applied to the arc-lamp for the purpose of keeping the electromotive force as constant as possible at the terminals of the incandescent lamps, which I place in series with the arc-lamp across constant-potential mains.

My invention may be embodied in many lamps of different forms, both the arc and the incandescent, and it is to be understood that I do not limit myself in any way to the exact mechanical construction of the arc-lamp described herein or any other devices, as many and various changes may be made without departing from its spirit and scope.

Reference is to be had to the annexed drawings, and to the letters marked thereon, form- 1natically,the different parts which go to make up my invention and their electrical connections. Fig. 2 is a front View of a combined arc and incandescent lamp, showing the preferred arrangement of parts.

Referring more particularly to Fig. 1, a source of electricity having mains across which a constant potential is given is represented by a. b and l) are the carbons of the arc-lamp. c is a small inner globe which incloses the carbons at the arc and serves to exclude the air by means of its tightness and the generation of gases by the are, as is well known. (Z is a clutch suitably pivoted by the hinge and pivot f. 9 represents amagnet or solenoid and core for operating the clutch, assisted by the spring and stop h. This form of an arc-lamp regulator being shown for the sake of clearness, the use of various other kinds of clutches and feeding arrangements capable of being operated by a magnet could be used. Thecoils of the magnet are connected in shunt with the incandescent lamps i, 2', i and and 2' said lamps being placed in series with the arc. j is a switch for turning the current on and off.

Referring to Fig. 2 it will be seen that I have shown the incandescent lamps i, 2", and 2' as fastened or affixed to the arc-lamp framework or cover part 7c. Z is the outer globe of the arc-lamp. The incandescent lamps are preferably placed around the top part of the arc-lamp or its framework and fastened to it by means of the sockets m.

While it is seen that I have shown a number of incandescent lamps connected in multiple, yet a single lamp capable of carrying the entire current would answer as well, and so would two or more lamps connected in series, as represented by 2' and 2'', provided their voltage and carrying capacity were of the proper amount.

' The action of the apparatus is as follows:

hen the switch j is in the position shown by the dotted lines-that is, with no current flowingthe carbons of the arc-lamp are together.

When the switch is turned on, the regulatingmagnet receives, practically, all the electromotive force which exists across the mains.

This high voltage (the magnet being designed to operate at the normal voltage the lamps require) instantly causes the magnet to sepa rate the carbons, thereby forming the arc and quickly reducing the potential at the lamps to the proper amount.

It is necessary for the successful operation of my invention that the regulating-magnet be placed in shunt-circuit to the incandescent lamp.sz'. 6., have its coils in shunt-circuit to said lamps-and that it be adjusted to feed the carbons together should the voltage across the incandescent lamps fall below an amount necessary to successfullyilluminate them and to separate the carbons should the voltage rise above an amount which the lamps are capable of resisting without injury. It will be seen that at the starting-point the carbons are together, and the incandescent lamps receive, pr.-rctically, the total pressure of the line, and as they are of much lower voltage than lamps designed to be operated directly across the line (usually about one-half to onefourth the voltage of the regular lamps) it would seem as if they would be injured; but I have found that the action of the regnlatirig-magnet when properly adjusted is so rapid in reducing the voltage to practically the amount required by the incandescent lamps as to render the effect of the momentary high voltage of no consequence, and as the voltage across the incandescent lamps is kept practically constant their illumination will be steady.

It will be seen that by using a shunt-magnet across the incandescent lamps for regulating the are a system of considerable flexibility is produced, for if any of the incandescent lamps are burned out or disconnected the only effect will be a proportionate decrease of current flowing and the candle-power of the arc, the respective voltages across the arc and the incandescent lamps remaining practically the same. Therefore the remaining lamps will be as successfully illuminated as before, with no dangerous increase of current through them, as would be the case if the magnet was in series with the lamps and any number be disconnected. Therefore it is clear that I am afforded ready means of varying the candlepower of my system by simply subtracting or adding to the number of incandescent lamps.

Not only is the illumination increased by the use of my system, but a better resistance is secured, for the reason that there is less heat effect and greater constancy on account of the lamps having the same temperature just after the current is turned on as after they have operated some time, due to the small mass to be heated, hence no change of resistance due to varying heat.

It will be seen that I have produced a system of electric lighting which has the advantage over the ordinary method of operating high-voltage arc-lamps across constant-potential mains by converting the dead resistance used therein into light, and thereby increasing the illumination available from a given amount of electrical energy.

By the term constant potential I mean an electromotive force which is commercially constant1'. c., not varying more than a few per cent. from the normal.

While I am aware that the use of incandescent lamps for resistance purposes is old and also the use of arc and incandescent lamps on the same circuit old, yet so far as I am aware the use of incandescent lamps for the double purpose of supplying a necessary resistance and for producing illumination, in conjunction with a regulating-magnet for maintaining a steady voltage across the incandescent lamps by means of changing the distance between two carbon points also used for illumination, the whole being placed across a constant-potential circuit, is novel and important, since it removes the great objection raised against the ordinary method of operating arc -lamps, as above set forthnamely, the great waste of electrical energy in the form of heat in the series resistance. For example, with an arc-lamp taking five amperes at one hundred and fifteen volts line pressure and seventy volts across the arc with the regulating-magnet I am able to operate five forty-five-volt one-ampere lamps with the surplus energy. The current through the regulating-magnet can be made so small as not to take any appreciable amount from the incandescent lamps. At a consumption of three watts per candle-power this will give a total of seventy-five candle-power, capable of efficient distribution in addition to the light received from the arc.

I-Iavin g thus explained the nature of my invention and described a way of constructing the same, though without attempting to set forth all the forms in which it may be made or all the modes of its use, it is declared that what is claimed is 1. The combination in an electric-lighting system of a constant-potential source of sup ply, an arc-lamp, an incandescent lamp or lamps in series with the arc of said arc-lamp, and a regulating-magnet applied to the arclamp having its coil or coils placedin a shunt circuit to the incandescent lamp or lamps.

2. The combination in an electric-lighting system of a constant-potential source of supply, an arc-lamp, an incandescent lamp or lamps in series with the arc of said arc-lamp, and a magnetic regulating device having its coil or coils placed in shunt-circuit to theincandescent lamp or lamps, said device being applied to the arc-lamp and arranged to maintain a constant potential across the terminals of the incandescent lamp or lamps by means of its action upon the arc of said arc-lamp.

3. The combination in an electric-lighting system of constant-potential supply-mains, an arc lamp, a plurality of incandescent lamps in multiple with each other and in series with the are of the arc-lamp across said supply-11mins, and a regnlatingqnagnet having its coil or coils in a shunt-circuit to the incandescent lamps, which magnet by its action in regulating the are of the arc-lamp maintains a constant potential across the terminnls of the incandescent lamps irrespective of the current flowing through the are or the number of incandescent lamps. v

RALPH O. HOOD.

itnesses:

L. W. KEITH,- O. E. WHIPPLE. 

